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Intermolecular hydrogen bonding in isostructural pincer complexes [OH-(t-BuPOCOPt-Bu)MCl] (M = Pd and Pt)

2019, Joksch, M., Spannenberg, A., Beweries, T.

In the crystal structure of the isostructural title compounds, namely {2,6-bis[(di-tert-butylphosphanyl)oxy]-4-hydroxyphenyl}chloridopalladium(II), [Pd(C22H39O3P2)Cl], 1, and {2,6-bis[(di-tert-butylphosphanyl)oxy]-4-hydroxyphenyl}chloridoplatinum(II), [Pt(C22H39O3P2)Cl], 2, the metal centres are coordinated in a distorted square-planar fashion by the POCOP pincer fragment and the chloride ligand. Both complexes form strong hydrogen-bonded chain structures through an interaction of the OH group in the 4-position of the aromatic POCOP backbone with the halide ligand.

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Crystal structure of di-n-but­yl­bis­([eta]5-penta­methyl­cyclo­penta­dien­yl)hafnium(IV)

2015, Arndt, Perdita, Schubert,Kathleen, Burlakov, Vladimir V., Spannenberg, Anke, Rosenthal, Uwe

The crystal structure of the title compound, [Hf(C10H15)2(C4H9)2], reveals two independent mol­ecules in the asymmetric unit. The diffraction experiment was performed with a racemically twinned crystal showing a 0.529 (5):0.471 (5) component ratio. Each HfIV atom is coordinated by two penta­methyl­cyclo­penta­dienyl and two n-butyl ligands in a distorted tetra­hedral geometry, with the cyclo­penta­dienyl rings inclined to one another by 45.11 (15) and 45.37 (16)°. In contrast to the isostructural di(n-butyl)bis([eta]5-penta­methyl­cyclo­penta­dien­yl)zirconium(IV) complex with a noticeable difference in the Zr-butyl bonding, the Hf-Cbut­yl bond lengths differ from each other by no more than 0.039 (3) Å.

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Crystal structure of (E)-pent-2-enoic acid

2015, Peppel, Tim, Sonneck, Marcel, Spannenberg, Anke, Wohlrab, Sebastian

The mol­ecule of the title compound, C5H8O2, a low-melting [alpha],[beta]-unsaturated carb­oxy­lic acid, is essentially planar [maximum displacement = 0.0239 (13) Å]. In the crystal, mol­ecules are linked into centrosymmetric dimers via pairs of O-H...O hydrogen bonds.

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Low-melting manganese(II)-based ionic liquids: Syntheses, structures, properties and influence of trace impurities

2019, Peppel, Tim, Geppert-Rybczyńska, Monika, Neise, Christin, Kragl, Udo, Köckerling, Martin

The synthesis of more than 10 new magnetic ionic liquids with [MnX4]2− anions, X = Cl, NCS, NCO, is presented. Detailed structural information through single-crystal X-ray diffraction is given for (DMDIm)[Mn(NCS)4], (BnEt3N)2[Mn(NCS)4], and {(Ph3P)2N}2[Mn(NCO4)]·0.6H2O, respectively. All compounds consist of discrete anions and cations with tetrahedrally coordinated Mn(II) atoms. They show paramagnetic behavior as expected for spin-only systems. Melting points are found for several systems below 100 °C classifying them as ionic liquids. Thermal properties are investigated using differential scanning calorimetry (DSC) measurements. The physicochemical properties of density, dynamic viscosity, electrolytic conductivity, and surface tension were measured temperature-dependent of selected samples. These properties are discussed in comparison to similar Co containing systems. An increasing amount of bromide impurity is found to affect the surface tension only up to 3.3%.

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Crystal structure of (E)-dodec-2-enoic acid

2015, Sonneck, Marcel, Peppel, Tim, Spannenberg, Anke, Wohlrab, Sebastian

The crystal structure of (E)-dodec-2-enoic acid, C12H22O2, an [alpha],[beta]-unsaturated carb­oxy­lic acid with a melting point (295 K) near room temperature, is characterized by carb­oxy­lic acid inversion dimers linked by pairs of O-H...O hydrogen bonds. The carb­oxy­lic acid group and the following three carbon atoms of the chain of the (E)-dodec-2-enoic acid mol­ecule lie almost in one plane (r.m.s. deviation for the four C atoms and two O atoms = 0.012 Å), whereas the remaining carbon atoms of the hydro­carbon chain adopt a nearly fully staggered conformation [moduli of torsion angles vary from 174.01 (13) to 179.97 (13)°].

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Crystal structure of bis(η5-cyclopenta-dienyl)(2, 3-diethylbutane-1, 4-diyl)-hafnium(IV)

2015, Burlakov, Vladimir V., Baumann, Wolfgang, Arndt, Perdita, Spannenberg, Anke, Rosenthal, Uwe

The title compound, [Hf(C5H5)2(C8H16)], proves a structural motif of hafna­cyclo­pentane besides the coordination of two cyclo­penta­dienyl ligands in an [eta]5-fashion. The hafna­cyclo­pentane ring has a twist conformation and is substituted by two ethyl groups in the [beta],[beta]'-positions, which are trans orientated to each other. One cyclo­penta­dienyl ring and one ethyl group are each disordered over two positions with site-occupancy ratios of 0.679 (15):0.321 (15) and 0.702 (18):0.298 (18), respectively.

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Crystal structure of (1S,2R,4S)-1-[(morpholin-4-yl)-methyl]-4-(prop-1-en-2-yl)cyclohexane-1,2-diol

2015, Outouch, Rachid, Oubaassine, Saadia, Ali, Mustapha Ait, El Firdoussi, Larbi, Spannenberg, Anke

The asymmetric unit of the title compound, C14H25NO3, contains two independent mol­ecules with similar geometry. The morpholine and cyclo­hexane rings of both mol­ecules adopt a chair conformation. Intra­molecular O-H...N hydrogen bonds are observed. In the crystal, mol­ecules are linked by O-H...O hydrogen bonds into chains parallel to the [101] direction. The chains are further connected through C-H...O hydrogen bonds forming undulating layers parallel to the (-101) plane. The absolute configuration was assigned by reference to an unchanging chiral centre in the synthetic procedure.

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Crystal structure of (E)-undec-2-enoic acid

2015, Sonneck, Marcel, Peppel, Tim, Spannenberg, Anke, Wohlrab, Sebastian

In the mol­ecule of the title low-melting [alpha],[beta]-unsaturated carb­oxy­lic acid, C11H20O2, the least-squares mean line through the octyl chain forms an angle of 60.10 (13)° with the normal to plane of the acrylic acid fragment (r.m.s. deviation = 0.008 Å). In the crystal, centrosymmetrically related mol­ecules are linked by pairs of O-H...O hydrogen bonds into dimers, forming layers parallel to the (041) plane.

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Crystal structure of (E)-hex-2-enoic acid

2015, Peppel, Tim, Sonneck, Marcel, Spannenberg, Anke, Wohlrab, Sebastian

The crystal structure of the title compound, C6H10O2, an [alpha],[beta]-unsaturated carb­oxy­lic acid, displays carb­oxy­lic acid inversion dimers linked by pairs of O-H...O hydrogen bonds. The packing is characterized by layers of acid dimers. All the non-H atoms of the (E)-hex-2-enoic acid mol­ecule lie almost in the same plane (r.m.s. deviation for the non-H atoms = 0.018 Å).

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Crystal structure of bis(η5-cyclopenta-dienyl)(1,4-di-tert-butylbuta-1-en-3-yn-1-yl) zirconium(IV) μ2-hydroxido-bis[tris-(pentafluorophenyl) borate]

2015, Burlakov, Vladimir V., Spannenberg, Anke, Arndt, Perdita, Rosenthal, Uwe

Alkyl zirconocene cations have been of considerable inter­est as reactive species in many polymerization processes. In the crystal structure of the title compound, [Zr(C12H19)(C5H5)2](C36HB2F30O), the [Zr(C5H5)2((t-Bu)C=C(H)-C2(t-Bu))]+ cation displays a buta-1-en-3-yne ligand side-on coordinated to a typical bent zirconocene [centroid(cp)-Zr-centroid(cp) = 131.4 (3)°, Zr-C(buta-1-en-3-yne) = 2.255 (3), 2.597 (3) and 2.452 (2) Å]. In the [HO(B(C6F5)3)2]- anion, intra­molecular O-H...F hydrogen bonds are observed. One tert-butyl group in the complex cation is disordered over two sets of sites with occupancies 0.701(4):0.299(4).